/* zlib.h -- interface of the 'zlib' general purpose compression library
   version 1.2.11, January 15th, 2017

   Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler

   This software is provided 'as-is', without any express or implied
   warranty.  In no event will the authors be held liable for any damages
   arising from the use of this software.

   Permission is granted to anyone to use this software for any purpose,
   including commercial applications, and to alter it and redistribute it
   freely, subject to the following restrictions:

   1. The origin of this software must not be misrepresented; you must not
   claim that you wrote the original software. If you use this software
   in a product, an acknowledgment in the product documentation would be
   appreciated but is not required.
   2. Altered source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.
   3. This notice may not be removed or altered from any source distribution.

   Jean-loup Gailly        Mark Adler
   jloup@gzip.org          madler@alumni.caltech.edu


   The data format used by the zlib library is described by RFCs (Request for
   Comments) 1950 to 1952 in the files http://tools.ietf.org/html/rfc1950
   (zlib format), rfc1951 (deflate format) and rfc1952 (gzip format).
   */

#ifndef ZLIB_H
#define ZLIB_H

#include "zconf.h"

#ifdef __cplusplus
extern "C" {
#endif

#define ZLIB_VERSION "1.2.11"
#define ZLIB_VERNUM 0x12b0
#define ZLIB_VER_MAJOR 1
#define ZLIB_VER_MINOR 2
#define ZLIB_VER_REVISION 11
#define ZLIB_VER_SUBREVISION 0

	/*
	   The 'zlib' compression library provides in-memory compression and
	   decompression functions, including integrity checks of the uncompressed data.
	   This version of the library supports only one compression method (deflation)
	   but other algorithms will be added later and will have the same stream
	   interface.

	   Compression can be done in a single step if the buffers are large enough,
	   or can be done by repeated calls of the compression function.  In the latter
	   case, the application must provide more input and/or consume the output
	   (providing more output space) before each call.

	   The compressed data format used by default by the in-memory functions is
	   the zlib format, which is a zlib wrapper documented in RFC 1950, wrapped
	   around a deflate stream, which is itself documented in RFC 1951.

	   The library also supports reading and writing files in gzip (.gz) format
	   with an interface similar to that of stdio using the functions that start
	   with "gz".  The gzip format is different from the zlib format.  gzip is a
	   gzip wrapper, documented in RFC 1952, wrapped around a deflate stream.

	   This library can optionally read and write gzip and raw deflate streams in
	   memory as well.

	   The zlib format was designed to be compact and fast for use in memory
	   and on communications channels.  The gzip format was designed for single-
	   file compression on file systems, has a larger header than zlib to maintain
	   directory information, and uses a different, slower check method than zlib.

	   The library does not install any signal handler.  The decoder checks
	   the consistency of the compressed data, so the library should never crash
	   even in the case of corrupted input.
	   */

	typedef voidpf (*alloc_func) OF((voidpf opaque, uInt items, uInt size));
	typedef void   (*free_func)  OF((voidpf opaque, voidpf address));

	struct internal_state;

	typedef struct z_stream_s {
		z_const Bytef *next_in;     /* next input byte */
		uInt     avail_in;  /* number of bytes available at next_in */
		uLong    total_in;  /* total number of input bytes read so far */

		Bytef    *next_out; /* next output byte will go here */
		uInt     avail_out; /* remaining free space at next_out */
		uLong    total_out; /* total number of bytes output so far */

		z_const char *msg;  /* last error message, NULL if no error */
		struct internal_state FAR *state; /* not visible by applications */

		alloc_func zalloc;  /* used to allocate the internal state */
		free_func  zfree;   /* used to free the internal state */
		voidpf     opaque;  /* private data object passed to zalloc and zfree */

		int     data_type;  /* best guess about the data type: binary or text
				       for deflate, or the decoding state for inflate */
		uLong   adler;      /* Adler-32 or CRC-32 value of the uncompressed data */
		uLong   reserved;   /* reserved for future use */
	} z_stream;

	typedef z_stream FAR *z_streamp;

	/*
	   gzip header information passed to and from zlib routines.  See RFC 1952
	   for more details on the meanings of these fields.
	   */
	typedef struct gz_header_s {
		int     text;       /* true if compressed data believed to be text */
		uLong   time;       /* modification time */
		int     xflags;     /* extra flags (not used when writing a gzip file) */
		int     os;         /* operating system */
		Bytef   *extra;     /* pointer to extra field or Z_NULL if none */
		uInt    extra_len;  /* extra field length (valid if extra != Z_NULL) */
		uInt    extra_max;  /* space at extra (only when reading header) */
		Bytef   *name;      /* pointer to zero-terminated file name or Z_NULL */
		uInt    name_max;   /* space at name (only when reading header) */
		Bytef   *comment;   /* pointer to zero-terminated comment or Z_NULL */
		uInt    comm_max;   /* space at comment (only when reading header) */
		int     hcrc;       /* true if there was or will be a header crc */
		int     done;       /* true when done reading gzip header (not used
				       when writing a gzip file) */
	} gz_header;

	typedef gz_header FAR *gz_headerp;

	/*
	   The application must update next_in and avail_in when avail_in has dropped
	   to zero.  It must update next_out and avail_out when avail_out has dropped
	   to zero.  The application must initialize zalloc, zfree and opaque before
	   calling the init function.  All other fields are set by the compression
	   library and must not be updated by the application.

	   The opaque value provided by the application will be passed as the first
	   parameter for calls of zalloc and zfree.  This can be useful for custom
	   memory management.  The compression library attaches no meaning to the
	   opaque value.

	   zalloc must return Z_NULL if there is not enough memory for the object.
	   If zlib is used in a multi-threaded application, zalloc and zfree must be
	   thread safe.  In that case, zlib is thread-safe.  When zalloc and zfree are
	   Z_NULL on entry to the initialization function, they are set to internal
	   routines that use the standard library functions malloc() and free().

	   On 16-bit systems, the functions zalloc and zfree must be able to allocate
	   exactly 65536 bytes, but will not be required to allocate more than this if
	   the symbol MAXSEG_64K is defined (see zconf.h).  WARNING: On MSDOS, pointers
	   returned by zalloc for objects of exactly 65536 bytes *must* have their
	   offset normalized to zero.  The default allocation function provided by this
	   library ensures this (see zutil.c).  To reduce memory requirements and avoid
	   any allocation of 64K objects, at the expense of compression ratio, compile
	   the library with -DMAX_WBITS=14 (see zconf.h).

	   The fields total_in and total_out can be used for statistics or progress
	   reports.  After compression, total_in holds the total size of the
	   uncompressed data and may be saved for use by the decompressor (particularly
	   if the decompressor wants to decompress everything in a single step).
	   */

	/* constants */

#define Z_NO_FLUSH      0
#define Z_PARTIAL_FLUSH 1
#define Z_SYNC_FLUSH    2
#define Z_FULL_FLUSH    3
#define Z_FINISH        4
#define Z_BLOCK         5
#define Z_TREES         6
	/* Allowed flush values; see deflate() and inflate() below for details */

#define Z_OK            0
#define Z_STREAM_END    1
#define Z_NEED_DICT     2
#define Z_ERRNO        (-1)
#define Z_STREAM_ERROR (-2)
#define Z_DATA_ERROR   (-3)
#define Z_MEM_ERROR    (-4)
#define Z_BUF_ERROR    (-5)
#define Z_VERSION_ERROR (-6)
	/* Return codes for the compression/decompression functions. Negative values
	 * are errors, positive values are used for special but normal events.
	 */

#define Z_NO_COMPRESSION         0
#define Z_BEST_SPEED             1
#define Z_BEST_COMPRESSION       9
#define Z_DEFAULT_COMPRESSION  (-1)
	/* compression levels */

#define Z_FILTERED            1
#define Z_HUFFMAN_ONLY        2
#define Z_RLE                 3
#define Z_FIXED               4
#define Z_DEFAULT_STRATEGY    0
	/* compression strategy; see deflateInit2() below for details */

#define Z_BINARY   0
#define Z_TEXT     1
#define Z_ASCII    Z_TEXT   /* for compatibility with 1.2.2 and earlier */
#define Z_UNKNOWN  2
	/* Possible values of the data_type field for deflate() */

#define Z_DEFLATED   8
	/* The deflate compression method (the only one supported in this version) */

#define Z_NULL  0  /* for initializing zalloc, zfree, opaque */

#define zlib_version zlibVersion()
	/* for compatibility with versions < 1.0.2 */


	/* basic functions */

	ZEXTERN const char * ZEXPORT zlibVersion OF((void));
	/* The application can compare zlibVersion and ZLIB_VERSION for consistency.
	   If the first character differs, the library code actually used is not
	   compatible with the zlib.h header file used by the application.  This check
	   is automatically made by deflateInit and inflateInit.
	   */

	/*
	   ZEXTERN int ZEXPORT deflateInit OF((z_streamp strm, int level));

	   Initializes the internal stream state for compression.  The fields
	   zalloc, zfree and opaque must be initialized before by the caller.  If
	   zalloc and zfree are set to Z_NULL, deflateInit updates them to use default
	   allocation functions.

	   The compression level must be Z_DEFAULT_COMPRESSION, or between 0 and 9:
	   1 gives best speed, 9 gives best compression, 0 gives no compression at all
	   (the input data is simply copied a block at a time).  Z_DEFAULT_COMPRESSION
	   requests a default compromise between speed and compression (currently
	   equivalent to level 6).

	   deflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
	   memory, Z_STREAM_ERROR if level is not a valid compression level, or
	   Z_VERSION_ERROR if the zlib library version (zlib_version) is incompatible
	   with the version assumed by the caller (ZLIB_VERSION).  msg is set to null
	   if there is no error message.  deflateInit does not perform any compression:
	   this will be done by deflate().
	   */


	ZEXTERN int ZEXPORT deflate OF((z_streamp strm, int flush));
	/*
	   deflate compresses as much data as possible, and stops when the input
	   buffer becomes empty or the output buffer becomes full.  It may introduce
	   some output latency (reading input without producing any output) except when
	   forced to flush.

	   The detailed semantics are as follows.  deflate performs one or both of the
	   following actions:

	   - Compress more input starting at next_in and update next_in and avail_in
	   accordingly.  If not all input can be processed (because there is not
	   enough room in the output buffer), next_in and avail_in are updated and
	   processing will resume at this point for the next call of deflate().

	   - Generate more output starting at next_out and update next_out and avail_out
	   accordingly.  This action is forced if the parameter flush is non zero.
	   Forcing flush frequently degrades the compression ratio, so this parameter
	   should be set only when necessary.  Some output may be provided even if
	   flush is zero.

	   Before the call of deflate(), the application should ensure that at least
	   one of the actions is possible, by providing more input and/or consuming more
	   output, and updating avail_in or avail_out accordingly; avail_out should
	   never be zero before the call.  The application can consume the compressed
	   output when it wants, for example when the output buffer is full (avail_out
	   == 0), or after each call of deflate().  If deflate returns Z_OK and with
	   zero avail_out, it must be called again after making room in the output
	   buffer because there might be more output pending. See deflatePending(),
	   which can be used if desired to determine whether or not there is more ouput
	   in that case.

	   Normally the parameter flush is set to Z_NO_FLUSH, which allows deflate to
	   decide how much data to accumulate before producing output, in order to
	   maximize compression.

	   If the parameter flush is set to Z_SYNC_FLUSH, all pending output is
	   flushed to the output buffer and the output is aligned on a byte boundary, so
	   that the decompressor can get all input data available so far.  (In
	   particular avail_in is zero after the call if enough output space has been
	   provided before the call.) Flushing may degrade compression for some
	   compression algorithms and so it should be used only when necessary.  This
	   completes the current deflate block and follows it with an empty stored block
	   that is three bits plus filler bits to the next byte, followed by four bytes
	   (00 00 ff ff).

	   If flush is set to Z_PARTIAL_FLUSH, all pending output is flushed to the
	   output buffer, but the output is not aligned to a byte boundary.  All of the
	   input data so far will be available to the decompressor, as for Z_SYNC_FLUSH.
	   This completes the current deflate block and follows it with an empty fixed
	   codes block that is 10 bits long.  This assures that enough bytes are output
	   in order for the decompressor to finish the block before the empty fixed
	   codes block.

	   If flush is set to Z_BLOCK, a deflate block is completed and emitted, as
	   for Z_SYNC_FLUSH, but the output is not aligned on a byte boundary, and up to
	   seven bits of the current block are held to be written as the next byte after
	   the next deflate block is completed.  In this case, the decompressor may not
	   be provided enough bits at this point in order to complete decompression of
	   the data provided so far to the compressor.  It may need to wait for the next
	   block to be emitted.  This is for advanced applications that need to control
	   the emission of deflate blocks.

	   If flush is set to Z_FULL_FLUSH, all output is flushed as with
	   Z_SYNC_FLUSH, and the compression state is reset so that decompression can
	   restart from this point if previous compressed data has been damaged or if
	   random access is desired.  Using Z_FULL_FLUSH too often can seriously degrade
	   compression.

	   If deflate returns with avail_out == 0, this function must be called again
	   with the same value of the flush parameter and more output space (updated
	   avail_out), until the flush is complete (deflate returns with non-zero
	avail_out).  In the case of a Z_FULL_FLUSH or Z_SYNC_FLUSH, make sure that
		avail_out is greater than six to avoid repeated flush markers due to
		avail_out == 0 on return.

		If the parameter flush is set to Z_FINISH, pending input is processed,
		   pending output is flushed and deflate returns with Z_STREAM_END if there was
			   enough output space.  If deflate returns with Z_OK or Z_BUF_ERROR, this
			   function must be called again with Z_FINISH and more output space (updated
					   avail_out) but no more input data, until it returns with Z_STREAM_END or an
			   error.  After deflate has returned Z_STREAM_END, the only possible operations
			   on the stream are deflateReset or deflateEnd.

			   Z_FINISH can be used in the first deflate call after deflateInit if all the
			   compression is to be done in a single step.  In order to complete in one
			   call, avail_out must be at least the value returned by deflateBound (see
					   below).  Then deflate is guaranteed to return Z_STREAM_END.  If not enough
			   output space is provided, deflate will not return Z_STREAM_END, and it must
			   be called again as described above.

			   deflate() sets strm->adler to the Adler-32 checksum of all input read
			   so far (that is, total_in bytes).  If a gzip stream is being generated, then
			   strm->adler will be the CRC-32 checksum of the input read so far.  (See
					   deflateInit2 below.)

			   deflate() may update strm->data_type if it can make a good guess about
			   the input data type (Z_BINARY or Z_TEXT).  If in doubt, the data is
			   considered binary.  This field is only for information purposes and does not
			   affect the compression algorithm in any manner.

			   deflate() returns Z_OK if some progress has been made (more input
					   processed or more output produced), Z_STREAM_END if all input has been
			   consumed and all output has been produced (only when flush is set to
					   Z_FINISH), Z_STREAM_ERROR if the stream state was inconsistent (for example
						   if next_in or next_out was Z_NULL or the state was inadvertently written over
						   by the application), or Z_BUF_ERROR if no progress is possible (for example
							   avail_in or avail_out was zero).  Note that Z_BUF_ERROR is not fatal, and
						   deflate() can be called again with more input and more output space to
						   continue compressing.
						   */


						   ZEXTERN int ZEXPORT deflateEnd OF((z_streamp strm));
	/*
	   All dynamically allocated data structures for this stream are freed.
	   This function discards any unprocessed input and does not flush any pending
	   output.

	   deflateEnd returns Z_OK if success, Z_STREAM_ERROR if the
	   stream state was inconsistent, Z_DATA_ERROR if the stream was freed
	   prematurely (some input or output was discarded).  In the error case, msg
	   may be set but then points to a static string (which must not be
	   deallocated).
	   */


	/*
	   ZEXTERN int ZEXPORT inflateInit OF((z_streamp strm));

	   Initializes the internal stream state for decompression.  The fields
	   next_in, avail_in, zalloc, zfree and opaque must be initialized before by
	   the caller.  In the current version of inflate, the provided input is not
	   read or consumed.  The allocation of a sliding window will be deferred to
	   the first call of inflate (if the decompression does not complete on the
	   first call).  If zalloc and zfree are set to Z_NULL, inflateInit updates
	   them to use default allocation functions.

	   inflateInit returns Z_OK if success, Z_MEM_ERROR if there was not enough
	   memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
	   version assumed by the caller, or Z_STREAM_ERROR if the parameters are
	   invalid, such as a null pointer to the structure.  msg is set to null if
	   there is no error message.  inflateInit does not perform any decompression.
	   Actual decompression will be done by inflate().  So next_in, and avail_in,
	   next_out, and avail_out are unused and unchanged.  The current
	   implementation of inflateInit() does not process any header information --
	   that is deferred until inflate() is called.
	   */


	ZEXTERN int ZEXPORT inflate OF((z_streamp strm, int flush, int check_crc));
	/*
	   inflate decompresses as much data as possible, and stops when the input
	   buffer becomes empty or the output buffer becomes full.  It may introduce
	   some output latency (reading input without producing any output) except when
	   forced to flush.

	   The detailed semantics are as follows.  inflate performs one or both of the
	   following actions:

	   - Decompress more input starting at next_in and update next_in and avail_in
	   accordingly.  If not all input can be processed (because there is not
	   enough room in the output buffer), then next_in and avail_in are updated
	   accordingly, and processing will resume at this point for the next call of
	   inflate().

	   - Generate more output starting at next_out and update next_out and avail_out
	   accordingly.  inflate() provides as much output as possible, until there is
	   no more input data or no more space in the output buffer (see below about
	   the flush parameter).

	   Before the call of inflate(), the application should ensure that at least
	   one of the actions is possible, by providing more input and/or consuming more
	   output, and updating the next_* and avail_* values accordingly.  If the
	   caller of inflate() does not provide both available input and available
	   output space, it is possible that there will be no progress made.  The
	   application can consume the uncompressed output when it wants, for example
	   when the output buffer is full (avail_out == 0), or after each call of
	   inflate().  If inflate returns Z_OK and with zero avail_out, it must be
	   called again after making room in the output buffer because there might be
	   more output pending.

	   The flush parameter of inflate() can be Z_NO_FLUSH, Z_SYNC_FLUSH, Z_FINISH,
	   Z_BLOCK, or Z_TREES.  Z_SYNC_FLUSH requests that inflate() flush as much
	   output as possible to the output buffer.  Z_BLOCK requests that inflate()
	   stop if and when it gets to the next deflate block boundary.  When decoding
	   the zlib or gzip format, this will cause inflate() to return immediately
	   after the header and before the first block.  When doing a raw inflate,
	   inflate() will go ahead and process the first block, and will return when it
	   gets to the end of that block, or when it runs out of data.

	   The Z_BLOCK option assists in appending to or combining deflate streams.
	   To assist in this, on return inflate() always sets strm->data_type to the
	   number of unused bits in the last byte taken from strm->next_in, plus 64 if
	   inflate() is currently decoding the last block in the deflate stream, plus
	   128 if inflate() returned immediately after decoding an end-of-block code or
	   decoding the complete header up to just before the first byte of the deflate
	   stream.  The end-of-block will not be indicated until all of the uncompressed
	   data from that block has been written to strm->next_out.  The number of
	   unused bits may in general be greater than seven, except when bit 7 of
	   data_type is set, in which case the number of unused bits will be less than
	   eight.  data_type is set as noted here every time inflate() returns for all
	   flush options, and so can be used to determine the amount of currently
	   consumed input in bits.

	   The Z_TREES option behaves as Z_BLOCK does, but it also returns when the
	   end of each deflate block header is reached, before any actual data in that
	   block is decoded.  This allows the caller to determine the length of the
	   deflate block header for later use in random access within a deflate block.
	   256 is added to the value of strm->data_type when inflate() returns
	   immediately after reaching the end of the deflate block header.

	   inflate() should normally be called until it returns Z_STREAM_END or an
	   error.  However if all decompression is to be performed in a single step (a
	   single call of inflate), the parameter flush should be set to Z_FINISH.  In
	   this case all pending input is processed and all pending output is flushed;
	   avail_out must be large enough to hold all of the uncompressed data for the
	   operation to complete.  (The size of the uncompressed data may have been
	   saved by the compressor for this purpose.)  The use of Z_FINISH is not
	   required to perform an inflation in one step.  However it may be used to
	   inform inflate that a faster approach can be used for the single inflate()
	   call.  Z_FINISH also informs inflate to not maintain a sliding window if the
	stream completes, which reduces inflate's memory footprint.  If the stream
		does not complete, either because not all of the stream is provided or not
		enough output space is provided, then a sliding window will be allocated and
		inflate() can be called again to continue the operation as if Z_NO_FLUSH had
		been used.

		In this implementation, inflate() always flushes as much output as
		possible to the output buffer, and always uses the faster approach on the
		first call.  So the effects of the flush parameter in this implementation are
		on the return value of inflate() as noted below, when inflate() returns early
		when Z_BLOCK or Z_TREES is used, and when inflate() avoids the allocation of
		memory for a sliding window when Z_FINISH is used.

		If a preset dictionary is needed after this call (see inflateSetDictionary
				below), inflate sets strm->adler to the Adler-32 checksum of the dictionary
		chosen by the compressor and returns Z_NEED_DICT; otherwise it sets
		strm->adler to the Adler-32 checksum of all output produced so far (that is,
				total_out bytes) and returns Z_OK, Z_STREAM_END or an error code as described
		below.  At the end of the stream, inflate() checks that its computed Adler-32
		checksum is equal to that saved by the compressor and returns Z_STREAM_END
		only if the checksum is correct.

		inflate() can decompress and check either zlib-wrapped or gzip-wrapped
		deflate data.  The header type is detected automatically, if requested when
		initializing with inflateInit2().  Any information contained in the gzip
		header is not retained unless inflateGetHeader() is used.  When processing
		gzip-wrapped deflate data, strm->adler32 is set to the CRC-32 of the output
		produced so far.  The CRC-32 is checked against the gzip trailer, as is the
		uncompressed length, modulo 2^32.

		inflate() returns Z_OK if some progress has been made (more input processed
				or more output produced), Z_STREAM_END if the end of the compressed data has
		been reached and all uncompressed output has been produced, Z_NEED_DICT if a
		preset dictionary is needed at this point, Z_DATA_ERROR if the input data was
		corrupted (input stream not conforming to the zlib format or incorrect check
				value, in which case strm->msg points to a string with a more specific
				error), Z_STREAM_ERROR if the stream structure was inconsistent (for example
					next_in or next_out was Z_NULL, or the state was inadvertently written over
					by the application), Z_MEM_ERROR if there was not enough memory, Z_BUF_ERROR
				if no progress was possible or if there was not enough room in the output
					buffer when Z_FINISH is used.  Note that Z_BUF_ERROR is not fatal, and
						inflate() can be called again with more input and more output space to
						continue decompressing.  If Z_DATA_ERROR is returned, the application may
						then call inflateSync() to look for a good compression block if a partial
						recovery of the data is to be attempted.
						*/


						ZEXTERN int ZEXPORT inflateEnd OF((z_streamp strm));
	/*
	   All dynamically allocated data structures for this stream are freed.
	   This function discards any unprocessed input and does not flush any pending
	   output.

	   inflateEnd returns Z_OK if success, or Z_STREAM_ERROR if the stream state
	   was inconsistent.
	   */


	/* Advanced functions */

	/*
	   The following functions are needed only in some special applications.
	   */

	/*
	   ZEXTERN int ZEXPORT deflateInit2 OF((z_streamp strm,
	   int  level,
	   int  method,
	   int  windowBits,
	   int  memLevel,
	   int  strategy));

	   This is another version of deflateInit with more compression options.  The
	   fields next_in, zalloc, zfree and opaque must be initialized before by the
	   caller.

	   The method parameter is the compression method.  It must be Z_DEFLATED in
	   this version of the library.

	   The windowBits parameter is the base two logarithm of the window size
	   (the size of the history buffer).  It should be in the range 8..15 for this
	   version of the library.  Larger values of this parameter result in better
	   compression at the expense of memory usage.  The default value is 15 if
	   deflateInit is used instead.

	   For the current implementation of deflate(), a windowBits value of 8 (a
	   window size of 256 bytes) is not supported.  As a result, a request for 8
	   will result in 9 (a 512-byte window).  In that case, providing 8 to
	   inflateInit2() will result in an error when the zlib header with 9 is
	   checked against the initialization of inflate().  The remedy is to not use 8
	   with deflateInit2() with this initialization, or at least in that case use 9
	   with inflateInit2().

	   windowBits can also be -8..-15 for raw deflate.  In this case, -windowBits
	   determines the window size.  deflate() will then generate raw deflate data
	   with no zlib header or trailer, and will not compute a check value.

	   windowBits can also be greater than 15 for optional gzip encoding.  Add
	   16 to windowBits to write a simple gzip header and trailer around the
	   compressed data instead of a zlib wrapper.  The gzip header will have no
	   file name, no extra data, no comment, no modification time (set to zero), no
	   header crc, and the operating system will be set to the appropriate value,
	   if the operating system was determined at compile time.  If a gzip stream is
	   being written, strm->adler is a CRC-32 instead of an Adler-32.

	   For raw deflate or gzip encoding, a request for a 256-byte window is
	   rejected as invalid, since only the zlib header provides a means of
	   transmitting the window size to the decompressor.

	   The memLevel parameter specifies how much memory should be allocated
	   for the internal compression state.  memLevel=1 uses minimum memory but is
	   slow and reduces compression ratio; memLevel=9 uses maximum memory for
	   optimal speed.  The default value is 8.  See zconf.h for total memory usage
	   as a function of windowBits and memLevel.

	   The strategy parameter is used to tune the compression algorithm.  Use the
	   value Z_DEFAULT_STRATEGY for normal data, Z_FILTERED for data produced by a
	   filter (or predictor), Z_HUFFMAN_ONLY to force Huffman encoding only (no
	   string match), or Z_RLE to limit match distances to one (run-length
	   encoding).  Filtered data consists mostly of small values with a somewhat
	   random distribution.  In this case, the compression algorithm is tuned to
	   compress them better.  The effect of Z_FILTERED is to force more Huffman
	   coding and less string matching; it is somewhat intermediate between
	   Z_DEFAULT_STRATEGY and Z_HUFFMAN_ONLY.  Z_RLE is designed to be almost as
	   fast as Z_HUFFMAN_ONLY, but give better compression for PNG image data.  The
	   strategy parameter only affects the compression ratio but not the
	   correctness of the compressed output even if it is not set appropriately.
	   Z_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler
	   decoder for special applications.

	   deflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
	   memory, Z_STREAM_ERROR if any parameter is invalid (such as an invalid
	   method), or Z_VERSION_ERROR if the zlib library version (zlib_version) is
	   incompatible with the version assumed by the caller (ZLIB_VERSION).  msg is
	   set to null if there is no error message.  deflateInit2 does not perform any
compression: this will be done by deflate().
		     */

		     ZEXTERN int ZEXPORT deflateSetDictionary OF((z_streamp strm,
					     const Bytef *dictionary,
					     uInt  dictLength));
	     /*
		Initializes the compression dictionary from the given byte sequence
		without producing any compressed output.  When using the zlib format, this
		function must be called immediately after deflateInit, deflateInit2 or
		deflateReset, and before any call of deflate.  When doing raw deflate, this
		function must be called either before any call of deflate, or immediately
		after the completion of a deflate block, i.e. after all input has been
		consumed and all output has been delivered when using any of the flush
		options Z_BLOCK, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH, or Z_FULL_FLUSH.  The
		compressor and decompressor must use exactly the same dictionary (see
		inflateSetDictionary).

		The dictionary should consist of strings (byte sequences) that are likely
		to be encountered later in the data to be compressed, with the most commonly
		used strings preferably put towards the end of the dictionary.  Using a
		dictionary is most useful when the data to be compressed is short and can be
		predicted with good accuracy; the data can then be compressed better than
		with the default empty dictionary.

		Depending on the size of the compression data structures selected by
		deflateInit or deflateInit2, a part of the dictionary may in effect be
		discarded, for example if the dictionary is larger than the window size
		provided in deflateInit or deflateInit2.  Thus the strings most likely to be
		useful should be put at the end of the dictionary, not at the front.  In
		addition, the current implementation of deflate will use at most the window
		size minus 262 bytes of the provided dictionary.

		Upon return of this function, strm->adler is set to the Adler-32 value
		of the dictionary; the decompressor may later use this value to determine
		which dictionary has been used by the compressor.  (The Adler-32 value
		applies to the whole dictionary even if only a subset of the dictionary is
		actually used by the compressor.) If a raw deflate was requested, then the
		Adler-32 value is not computed and strm->adler is not set.

		deflateSetDictionary returns Z_OK if success, or Z_STREAM_ERROR if a
		parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
		inconsistent (for example if deflate has already been called for this stream
		or if not at a block boundary for raw deflate).  deflateSetDictionary does
		not perform any compression: this will be done by deflate().
		*/

	     ZEXTERN int ZEXPORT deflateGetDictionary OF((z_streamp strm,
				     Bytef *dictionary,
				     uInt  *dictLength));
	     /*
		Returns the sliding dictionary being maintained by deflate.  dictLength is
		set to the number of bytes in the dictionary, and that many bytes are copied
		to dictionary.  dictionary must have enough space, where 32768 bytes is
		always enough.  If deflateGetDictionary() is called with dictionary equal to
		Z_NULL, then only the dictionary length is returned, and nothing is copied.
		Similary, if dictLength is Z_NULL, then it is not set.

		deflateGetDictionary() may return a length less than the window size, even
		when more than the window size in input has been provided. It may return up
		to 258 bytes less in that case, due to how zlib's implementation of deflate
		manages the sliding window and lookahead for matches, where matches can be
		up to 258 bytes long. If the application needs the last window-size bytes of
		input, then that would need to be saved by the application outside of zlib.

		deflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
		stream state is inconsistent.
		*/

	     ZEXTERN int ZEXPORT deflateCopy OF((z_streamp dest,
				     z_streamp source));
	     /*
		Sets the destination stream as a complete copy of the source stream.

		This function can be useful when several compression strategies will be
		tried, for example when there are several ways of pre-processing the input
		data with a filter.  The streams that will be discarded should then be freed
		by calling deflateEnd.  Note that deflateCopy duplicates the internal
		compression state which can be quite large, so this strategy is slow and can
		consume lots of memory.

		deflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
		enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
		(such as zalloc being Z_NULL).  msg is left unchanged in both source and
		destination.
		*/

	     ZEXTERN int ZEXPORT deflateReset OF((z_streamp strm));
	     /*
		This function is equivalent to deflateEnd followed by deflateInit, but
		does not free and reallocate the internal compression state.  The stream
		will leave the compression level and any other attributes that may have been
		set unchanged.

		deflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent (such as zalloc or state being Z_NULL).
		*/

	     ZEXTERN int ZEXPORT deflateParams OF((z_streamp strm,
				     int level,
				     int strategy));
	     /*
		Dynamically update the compression level and compression strategy.  The
		interpretation of level and strategy is as in deflateInit2().  This can be
		used to switch between compression and straight copy of the input data, or
		to switch to a different kind of input data requiring a different strategy.
		If the compression approach (which is a function of the level) or the
		strategy is changed, and if any input has been consumed in a previous
		deflate() call, then the input available so far is compressed with the old
		level and strategy using deflate(strm, Z_BLOCK).  There are three approaches
		for the compression levels 0, 1..3, and 4..9 respectively.  The new level
		and strategy will take effect at the next call of deflate().

		If a deflate(strm, Z_BLOCK) is performed by deflateParams(), and it does
		not have enough output space to complete, then the parameter change will not
		take effect.  In this case, deflateParams() can be called again with the
		same parameters and more output space to try again.

		In order to assure a change in the parameters on the first try, the
		deflate stream should be flushed using deflate() with Z_BLOCK or other flush
		request until strm.avail_out is not zero, before calling deflateParams().
		Then no more input data should be provided before the deflateParams() call.
		If this is done, the old level and strategy will be applied to the data
		compressed before deflateParams(), and the new level and strategy will be
		applied to the the data compressed after deflateParams().

		deflateParams returns Z_OK on success, Z_STREAM_ERROR if the source stream
		state was inconsistent or if a parameter was invalid, or Z_BUF_ERROR if
		there was not enough output space to complete the compression of the
		available input data before a change in the strategy or approach.  Note that
		in the case of a Z_BUF_ERROR, the parameters are not changed.  A return
		value of Z_BUF_ERROR is not fatal, in which case deflateParams() can be
		retried with more output space.
		*/

	     ZEXTERN int ZEXPORT deflateTune OF((z_streamp strm,
				     int good_length,
				     int max_lazy,
				     int nice_length,
				     int max_chain));
	     /*
		Fine tune deflate's internal compression parameters.  This should only be
		used by someone who understands the algorithm used by zlib's deflate for
		searching for the best matching string, and even then only by the most
		fanatic optimizer trying to squeeze out the last compressed bit for their
		specific input data.  Read the deflate.c source code for the meaning of the
		max_lazy, good_length, nice_length, and max_chain parameters.

		deflateTune() can be called after deflateInit() or deflateInit2(), and
		returns Z_OK on success, or Z_STREAM_ERROR for an invalid deflate stream.
		*/

	     ZEXTERN uLong ZEXPORT deflateBound OF((z_streamp strm,
				     uLong sourceLen));
	     /*
		deflateBound() returns an upper bound on the compressed size after
		deflation of sourceLen bytes.  It must be called after deflateInit() or
		deflateInit2(), and after deflateSetHeader(), if used.  This would be used
		to allocate an output buffer for deflation in a single pass, and so would be
		called before deflate().  If that first deflate() call is provided the
		sourceLen input bytes, an output buffer allocated to the size returned by
		deflateBound(), and the flush value Z_FINISH, then deflate() is guaranteed
		to return Z_STREAM_END.  Note that it is possible for the compressed size to
		be larger than the value returned by deflateBound() if flush options other
		than Z_FINISH or Z_NO_FLUSH are used.
		*/

	     ZEXTERN int ZEXPORT deflatePending OF((z_streamp strm,
				     unsigned *pending,
				     int *bits));
	     /*
		deflatePending() returns the number of bytes and bits of output that have
		been generated, but not yet provided in the available output.  The bytes not
		provided would be due to the available output space having being consumed.
		The number of bits of output not provided are between 0 and 7, where they
		await more bits to join them in order to fill out a full byte.  If pending
		or bits are Z_NULL, then those values are not set.

		deflatePending returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent.
		*/

	     ZEXTERN int ZEXPORT deflatePrime OF((z_streamp strm,
				     int bits,
				     int value));
	     /*
		deflatePrime() inserts bits in the deflate output stream.  The intent
		is that this function is used to start off the deflate output with the bits
		leftover from a previous deflate stream when appending to it.  As such, this
		function can only be used for raw deflate, and must be used before the first
		deflate() call after a deflateInit2() or deflateReset().  bits must be less
		than or equal to 16, and that many of the least significant bits of value
		will be inserted in the output.

		deflatePrime returns Z_OK if success, Z_BUF_ERROR if there was not enough
		room in the internal buffer to insert the bits, or Z_STREAM_ERROR if the
		source stream state was inconsistent.
		*/

	     ZEXTERN int ZEXPORT deflateSetHeader OF((z_streamp strm,
				     gz_headerp head));
	     /*
		deflateSetHeader() provides gzip header information for when a gzip
		stream is requested by deflateInit2().  deflateSetHeader() may be called
		after deflateInit2() or deflateReset() and before the first call of
		deflate().  The text, time, os, extra field, name, and comment information
		in the provided gz_header structure are written to the gzip header (xflag is
		ignored -- the extra flags are set according to the compression level).  The
		caller must assure that, if not Z_NULL, name and comment are terminated with
		a zero byte, and that if extra is not Z_NULL, that extra_len bytes are
		available there.  If hcrc is true, a gzip header crc is included.  Note that
		the current versions of the command-line version of gzip (up through version
		1.3.x) do not support header crc's, and will report that it is a "multi-part
		gzip file" and give up.

		If deflateSetHeader is not used, the default gzip header has text false,
		the time set to zero, and os set to 255, with no extra, name, or comment
		fields.  The gzip header is returned to the default state by deflateReset().

		deflateSetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent.
		*/

	     /*
		ZEXTERN int ZEXPORT inflateInit2 OF((z_streamp strm,
		int  windowBits));

		This is another version of inflateInit with an extra parameter.  The
		fields next_in, avail_in, zalloc, zfree and opaque must be initialized
		before by the caller.

		The windowBits parameter is the base two logarithm of the maximum window
		size (the size of the history buffer).  It should be in the range 8..15 for
		this version of the library.  The default value is 15 if inflateInit is used
		instead.  windowBits must be greater than or equal to the windowBits value
		provided to deflateInit2() while compressing, or it must be equal to 15 if
		deflateInit2() was not used.  If a compressed stream with a larger window
		size is given as input, inflate() will return with the error code
		Z_DATA_ERROR instead of trying to allocate a larger window.

		windowBits can also be zero to request that inflate use the window size in
		the zlib header of the compressed stream.

		windowBits can also be -8..-15 for raw inflate.  In this case, -windowBits
		determines the window size.  inflate() will then process raw deflate data,
		not looking for a zlib or gzip header, not generating a check value, and not
		looking for any check values for comparison at the end of the stream.  This
		is for use with other formats that use the deflate compressed data format
		such as zip.  Those formats provide their own check values.  If a custom
		format is developed using the raw deflate format for compressed data, it is
		recommended that a check value such as an Adler-32 or a CRC-32 be applied to
		the uncompressed data as is done in the zlib, gzip, and zip formats.  For
		most applications, the zlib format should be used as is.  Note that comments
		above on the use in deflateInit2() applies to the magnitude of windowBits.

		windowBits can also be greater than 15 for optional gzip decoding.  Add
		32 to windowBits to enable zlib and gzip decoding with automatic header
		detection, or add 16 to decode only the gzip format (the zlib format will
		return a Z_DATA_ERROR).  If a gzip stream is being decoded, strm->adler is a
		CRC-32 instead of an Adler-32.  Unlike the gunzip utility and gzread() (see
		below), inflate() will not automatically decode concatenated gzip streams.
		inflate() will return Z_STREAM_END at the end of the gzip stream.  The state
		would need to be reset to continue decoding a subsequent gzip stream.

		inflateInit2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
		memory, Z_VERSION_ERROR if the zlib library version is incompatible with the
		version assumed by the caller, or Z_STREAM_ERROR if the parameters are
		invalid, such as a null pointer to the structure.  msg is set to null if
		there is no error message.  inflateInit2 does not perform any decompression
		apart from possibly reading the zlib header if present: actual decompression
		will be done by inflate().  (So next_in and avail_in may be modified, but
		next_out and avail_out are unused and unchanged.) The current implementation
		of inflateInit2() does not process any header information -- that is
		deferred until inflate() is called.
		*/

	     ZEXTERN int ZEXPORT inflateSetDictionary OF((z_streamp strm,
				     const Bytef *dictionary,
				     uInt  dictLength));
	     /*
		Initializes the decompression dictionary from the given uncompressed byte
		sequence.  This function must be called immediately after a call of inflate,
		if that call returned Z_NEED_DICT.  The dictionary chosen by the compressor
		can be determined from the Adler-32 value returned by that call of inflate.
		The compressor and decompressor must use exactly the same dictionary (see
		deflateSetDictionary).  For raw inflate, this function can be called at any
		time to set the dictionary.  If the provided dictionary is smaller than the
		window and there is already data in the window, then the provided dictionary
		will amend what's there.  The application must insure that the dictionary
		that was used for compression is provided.

		inflateSetDictionary returns Z_OK if success, Z_STREAM_ERROR if a
		parameter is invalid (e.g.  dictionary being Z_NULL) or the stream state is
		inconsistent, Z_DATA_ERROR if the given dictionary doesn't match the
		expected one (incorrect Adler-32 value).  inflateSetDictionary does not
		perform any decompression: this will be done by subsequent calls of
		inflate().
		*/

	     ZEXTERN int ZEXPORT inflateGetDictionary OF((z_streamp strm,
				     Bytef *dictionary,
				     uInt  *dictLength));
	     /*
		Returns the sliding dictionary being maintained by inflate.  dictLength is
		set to the number of bytes in the dictionary, and that many bytes are copied
		to dictionary.  dictionary must have enough space, where 32768 bytes is
		always enough.  If inflateGetDictionary() is called with dictionary equal to
		Z_NULL, then only the dictionary length is returned, and nothing is copied.
		Similary, if dictLength is Z_NULL, then it is not set.

		inflateGetDictionary returns Z_OK on success, or Z_STREAM_ERROR if the
		stream state is inconsistent.
		*/

	     ZEXTERN int ZEXPORT inflateSync OF((z_streamp strm));
	     /*
		Skips invalid compressed data until a possible full flush point (see above
		for the description of deflate with Z_FULL_FLUSH) can be found, or until all
		available input is skipped.  No output is provided.

		inflateSync searches for a 00 00 FF FF pattern in the compressed data.
		All full flush points have this pattern, but not all occurrences of this
		pattern are full flush points.

		inflateSync returns Z_OK if a possible full flush point has been found,
		Z_BUF_ERROR if no more input was provided, Z_DATA_ERROR if no flush point
		has been found, or Z_STREAM_ERROR if the stream structure was inconsistent.
		In the success case, the application may save the current current value of
		total_in which indicates where valid compressed data was found.  In the
		error case, the application may repeatedly call inflateSync, providing more
		input each time, until success or end of the input data.
		*/

	     ZEXTERN int ZEXPORT inflateCopy OF((z_streamp dest,
				     z_streamp source));
	     /*
		Sets the destination stream as a complete copy of the source stream.

		This function can be useful when randomly accessing a large stream.  The
		first pass through the stream can periodically record the inflate state,
		allowing restarting inflate at those points when randomly accessing the
		stream.

		inflateCopy returns Z_OK if success, Z_MEM_ERROR if there was not
		enough memory, Z_STREAM_ERROR if the source stream state was inconsistent
		(such as zalloc being Z_NULL).  msg is left unchanged in both source and
		destination.
		*/

	     ZEXTERN int ZEXPORT inflateReset OF((z_streamp strm));
	     /*
		This function is equivalent to inflateEnd followed by inflateInit,
		but does not free and reallocate the internal decompression state.  The
		stream will keep attributes that may have been set by inflateInit2.

		inflateReset returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent (such as zalloc or state being Z_NULL).
		*/

	     ZEXTERN int ZEXPORT inflateReset2 OF((z_streamp strm,
				     int windowBits));
	     /*
		This function is the same as inflateReset, but it also permits changing
		the wrap and window size requests.  The windowBits parameter is interpreted
		the same as it is for inflateInit2.  If the window size is changed, then the
		memory allocated for the window is freed, and the window will be reallocated
		by inflate() if needed.

		inflateReset2 returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent (such as zalloc or state being Z_NULL), or if
		the windowBits parameter is invalid.
		*/

	     ZEXTERN int ZEXPORT inflatePrime OF((z_streamp strm,
				     int bits,
				     int value));
	     /*
		This function inserts bits in the inflate input stream.  The intent is
		that this function is used to start inflating at a bit position in the
		middle of a byte.  The provided bits will be used before any bytes are used
		from next_in.  This function should only be used with raw inflate, and
		should be used before the first inflate() call after inflateInit2() or
		inflateReset().  bits must be less than or equal to 16, and that many of the
		least significant bits of value will be inserted in the input.

		If bits is negative, then the input stream bit buffer is emptied.  Then
		inflatePrime() can be called again to put bits in the buffer.  This is used
		to clear out bits leftover after feeding inflate a block description prior
		to feeding inflate codes.

		inflatePrime returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent.
		*/

	     ZEXTERN long ZEXPORT inflateMark OF((z_streamp strm));
	     /*
		This function returns two values, one in the lower 16 bits of the return
		value, and the other in the remaining upper bits, obtained by shifting the
		return value down 16 bits.  If the upper value is -1 and the lower value is
		zero, then inflate() is currently decoding information outside of a block.
		If the upper value is -1 and the lower value is non-zero, then inflate is in
		the middle of a stored block, with the lower value equaling the number of
		bytes from the input remaining to copy.  If the upper value is not -1, then
		it is the number of bits back from the current bit position in the input of
		the code (literal or length/distance pair) currently being processed.  In
		that case the lower value is the number of bytes already emitted for that
		code.

		A code is being processed if inflate is waiting for more input to complete
		decoding of the code, or if it has completed decoding but is waiting for
		more output space to write the literal or match data.

		inflateMark() is used to mark locations in the input data for random
		access, which may be at bit positions, and to note those cases where the
		output of a code may span boundaries of random access blocks.  The current
		location in the input stream can be determined from avail_in and data_type
		as noted in the description for the Z_BLOCK flush parameter for inflate.

		inflateMark returns the value noted above, or -65536 if the provided
		source stream state was inconsistent.
		*/

	     ZEXTERN int ZEXPORT inflateGetHeader OF((z_streamp strm,
				     gz_headerp head));
	     /*
		inflateGetHeader() requests that gzip header information be stored in the
		provided gz_header structure.  inflateGetHeader() may be called after
		inflateInit2() or inflateReset(), and before the first call of inflate().
		As inflate() processes the gzip stream, head->done is zero until the header
		is completed, at which time head->done is set to one.  If a zlib stream is
		being decoded, then head->done is set to -1 to indicate that there will be
		no gzip header information forthcoming.  Note that Z_BLOCK or Z_TREES can be
		used to force inflate() to return immediately after header processing is
		complete and before any actual data is decompressed.

		The text, time, xflags, and os fields are filled in with the gzip header
		contents.  hcrc is set to true if there is a header CRC.  (The header CRC
		was valid if done is set to one.) If extra is not Z_NULL, then extra_max
		contains the maximum number of bytes to write to extra.  Once done is true,
		extra_len contains the actual extra field length, and extra contains the
		extra field, or that field truncated if extra_max is less than extra_len.
		If name is not Z_NULL, then up to name_max characters are written there,
		terminated with a zero unless the length is greater than name_max.  If
		comment is not Z_NULL, then up to comm_max characters are written there,
		terminated with a zero unless the length is greater than comm_max.  When any
		of extra, name, or comment are not Z_NULL and the respective field is not
		present in the header, then that field is set to Z_NULL to signal its
		absence.  This allows the use of deflateSetHeader() with the returned
		structure to duplicate the header.  However if those fields are set to
		allocated memory, then the application will need to save those pointers
		elsewhere so that they can be eventually freed.

		If inflateGetHeader is not used, then the header information is simply
		discarded.  The header is always checked for validity, including the header
		CRC if present.  inflateReset() will reset the process to discard the header
		information.  The application would need to call inflateGetHeader() again to
		retrieve the header from the next gzip stream.

		inflateGetHeader returns Z_OK if success, or Z_STREAM_ERROR if the source
		stream state was inconsistent.
		*/

	     /*
		ZEXTERN int ZEXPORT inflateBackInit OF((z_streamp strm, int windowBits,
		unsigned char FAR *window));

		Initialize the internal stream state for decompression using inflateBack()
		calls.  The fields zalloc, zfree and opaque in strm must be initialized
		before the call.  If zalloc and zfree are Z_NULL, then the default library-
		derived memory allocation routines are used.  windowBits is the base two
		logarithm of the window size, in the range 8..15.  window is a caller
		supplied buffer of that size.  Except for special applications where it is
		assured that deflate was used with small window sizes, windowBits must be 15
		and a 32K byte window must be supplied to be able to decompress general
		deflate streams.

		See inflateBack() for the usage of these routines.

		inflateBackInit will return Z_OK on success, Z_STREAM_ERROR if any of
		the parameters are invalid, Z_MEM_ERROR if the internal state could not be
		allocated, or Z_VERSION_ERROR if the version of the library does not match
		the version of the header file.
		*/

	     typedef unsigned (*in_func) OF((void FAR *,
				     z_const unsigned char FAR * FAR *));
	     typedef int (*out_func) OF((void FAR *, unsigned char FAR *, unsigned));

	     ZEXTERN int ZEXPORT inflateBack OF((z_streamp strm,
				     in_func in, void FAR *in_desc,
				     out_func out, void FAR *out_desc));
	     /*
		inflateBack() does a raw inflate with a single call using a call-back
		interface for input and output.  This is potentially more efficient than
		inflate() for file i/o applications, in that it avoids copying between the
		output and the sliding window by simply making the window itself the output
		buffer.  inflate() can be faster on modern CPUs when used with large
		buffers.  inflateBack() trusts the application to not change the output
		buffer passed by the output function, at least until inflateBack() returns.

		inflateBackInit() must be called first to allocate the internal state
		and to initialize the state with the user-provided window buffer.
		inflateBack() may then be used multiple times to inflate a complete, raw
		deflate stream with each call.  inflateBackEnd() is then called to free the
		allocated state.

		A raw deflate stream is one with no zlib or gzip header or trailer.
		This routine would normally be used in a utility that reads zip or gzip
		files and writes out uncompressed files.  The utility would decode the
		header and process the trailer on its own, hence this routine expects only
		the raw deflate stream to decompress.  This is different from the default
		behavior of inflate(), which expects a zlib header and trailer around the
		deflate stream.

		inflateBack() uses two subroutines supplied by the caller that are then
		called by inflateBack() for input and output.  inflateBack() calls those
		routines until it reads a complete deflate stream and writes out all of the
		uncompressed data, or until it encounters an error.  The function's
		parameters and return types are defined above in the in_func and out_func
		typedefs.  inflateBack() will call in(in_desc, &buf) which should return the
		number of bytes of provided input, and a pointer to that input in buf.  If
		there is no input available, in() must return zero -- buf is ignored in that
		case -- and inflateBack() will return a buffer error.  inflateBack() will
		call out(out_desc, buf, len) to write the uncompressed data buf[0..len-1].
		out() should return zero on success, or non-zero on failure.  If out()
		returns non-zero, inflateBack() will return with an error.  Neither in() nor
		out() are permitted to change the contents of the window provided to
		inflateBackInit(), which is also the buffer that out() uses to write from.
		The length written by out() will be at most the window size.  Any non-zero
		amount of input may be provided by in().

		For convenience, inflateBack() can be provided input on the first call by
		setting strm->next_in and strm->avail_in.  If that input is exhausted, then
		in() will be called.  Therefore strm->next_in must be initialized before
		calling inflateBack().  If strm->next_in is Z_NULL, then in() will be called
		immediately for input.  If strm->next_in is not Z_NULL, then strm->avail_in
		must also be initialized, and then if strm->avail_in is not zero, input will
		initially be taken from strm->next_in[0 ..  strm->avail_in - 1].

		The in_desc and out_desc parameters of inflateBack() is passed as the
		first parameter of in() and out() respectively when they are called.  These
		descriptors can be optionally used to pass any information that the caller-
		supplied in() and out() functions need to do their job.

		On return, inflateBack() will set strm->next_in and strm->avail_in to
		pass back any unused input that was provided by the last in() call.  The
		return values of inflateBack() can be Z_STREAM_END on success, Z_BUF_ERROR
		if in() or out() returned an error, Z_DATA_ERROR if there was a format error
		in the deflate stream (in which case strm->msg is set to indicate the nature
		of the error), or Z_STREAM_ERROR if the stream was not properly initialized.
		In the case of Z_BUF_ERROR, an input or output error can be distinguished
		using strm->next_in which will be Z_NULL only if in() returned an error.  If
		strm->next_in is not Z_NULL, then the Z_BUF_ERROR was due to out() returning
		non-zero.  (in() will always be called before out(), so strm->next_in is
		assured to be defined if out() returns non-zero.)  Note that inflateBack()
		cannot return Z_OK.
		*/

	     ZEXTERN int ZEXPORT inflateBackEnd OF((z_streamp strm));
	     /*
		All memory allocated by inflateBackInit() is freed.

		inflateBackEnd() returns Z_OK on success, or Z_STREAM_ERROR if the stream
		state was inconsistent.
		*/

	     ZEXTERN uLong ZEXPORT zlibCompileFlags OF((void));
	     /* Return flags indicating compile-time options.

		Type sizes, two bits each, 00 = 16 bits, 01 = 32, 10 = 64, 11 = other:
		1.0: size of uInt
		3.2: size of uLong
		5.4: size of voidpf (pointer)
		7.6: size of z_off_t

		Compiler, assembler, and debug options:
8: ZLIB_DEBUG
9: ASMV or ASMINF -- use ASM code
10: ZLIB_WINAPI -- exported functions use the WINAPI calling convention
11: 0 (reserved)

One-time table building (smaller code, but not thread-safe if true):
12: BUILDFIXED -- build static block decoding tables when needed
13: DYNAMIC_CRC_TABLE -- build CRC calculation tables when needed
14,15: 0 (reserved)

Library content (indicates missing functionality):
16: NO_GZCOMPRESS -- gz* functions cannot compress (to avoid linking
deflate code when not needed)
17: NO_GZIP -- deflate can't write gzip streams, and inflate can't detect
and decode gzip streams (to avoid linking crc code)
18-19: 0 (reserved)

Operation variations (changes in library functionality):
20: PKZIP_BUG_WORKAROUND -- slightly more permissive inflate
21: FASTEST -- deflate algorithm with only one, lowest compression level
22,23: 0 (reserved)

The sprintf variant used by gzprintf (zero is best):
24: 0 = vs*, 1 = s* -- 1 means limited to 20 arguments after the format
25: 0 = *nprintf, 1 = *printf -- 1 means gzprintf() not secure!
26: 0 = returns value, 1 = void -- 1 means inferred string length returned

Remainder:
27-31: 0 (reserved)
*/

#ifndef Z_SOLO

	     /* utility functions */

	     /*
		The following utility functions are implemented on top of the basic
		stream-oriented functions.  To simplify the interface, some default options
		are assumed (compression level and memory usage, standard memory allocation
		functions).  The source code of these utility functions can be modified if
		you need special options.
		*/

	     ZEXTERN int ZEXPORT compress OF((Bytef *dest,   uLongf *destLen,
				     const Bytef *source, uLong sourceLen));
	     /*
		Compresses the source buffer into the destination buffer.  sourceLen is
		the byte length of the source buffer.  Upon entry, destLen is the total size
		of the destination buffer, which must be at least the value returned by
		compressBound(sourceLen).  Upon exit, destLen is the actual size of the
		compressed data.  compress() is equivalent to compress2() with a level
		parameter of Z_DEFAULT_COMPRESSION.

		compress returns Z_OK if success, Z_MEM_ERROR if there was not
		enough memory, Z_BUF_ERROR if there was not enough room in the output
		buffer.
		*/

	     ZEXTERN int ZEXPORT compress2 OF((Bytef *dest,   uLongf *destLen,
				     const Bytef *source, uLong sourceLen,
				     int level));
	     /*
		Compresses the source buffer into the destination buffer.  The level
		parameter has the same meaning as in deflateInit.  sourceLen is the byte
		length of the source buffer.  Upon entry, destLen is the total size of the
		destination buffer, which must be at least the value returned by
		compressBound(sourceLen).  Upon exit, destLen is the actual size of the
		compressed data.

		compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough
		memory, Z_BUF_ERROR if there was not enough room in the output buffer,
		Z_STREAM_ERROR if the level parameter is invalid.
		*/

	     ZEXTERN uLong ZEXPORT compressBound OF((uLong sourceLen));
	     /*
		compressBound() returns an upper bound on the compressed size after
		compress() or compress2() on sourceLen bytes.  It would be used before a
		compress() or compress2() call to allocate the destination buffer.
		*/

	     ZEXTERN int ZEXPORT uncompress OF((Bytef *dest,   uLongf *destLen,
				     const Bytef *source, uLong sourceLen));
	     /*
		Decompresses the source buffer into the destination buffer.  sourceLen is
		the byte length of the source buffer.  Upon entry, destLen is the total size
		of the destination buffer, which must be large enough to hold the entire
		uncompressed data.  (The size of the uncompressed data must have been saved
		previously by the compressor and transmitted to the decompressor by some
		mechanism outside the scope of this compression library.) Upon exit, destLen
		is the actual size of the uncompressed data.

		uncompress returns Z_OK if success, Z_MEM_ERROR if there was not
		enough memory, Z_BUF_ERROR if there was not enough room in the output
		buffer, or Z_DATA_ERROR if the input data was corrupted or incomplete.  In
		the case where there is not enough room, uncompress() will fill the output
		buffer with the uncompressed data up to that point.
		*/

	     ZEXTERN int ZEXPORT uncompress2 OF((Bytef *dest,   uLongf *destLen,
				     const Bytef *source, uLong *sourceLen));
	     /*
		Same as uncompress, except that sourceLen is a pointer, where the
		length of the source is *sourceLen.  On return, *sourceLen is the number of
		source bytes consumed.
		*/

	     /* gzip file access functions */

	     /*
		This library supports reading and writing files in gzip (.gz) format with
		an interface similar to that of stdio, using the functions that start with
		"gz".  The gzip format is different from the zlib format.  gzip is a gzip
		wrapper, documented in RFC 1952, wrapped around a deflate stream.
		*/

	     typedef struct gzFile_s *gzFile;    /* semi-opaque gzip file descriptor */

	     /*
		ZEXTERN gzFile ZEXPORT gzopen OF((const char *path, const char *mode));

		Opens a gzip (.gz) file for reading or writing.  The mode parameter is as
		in fopen ("rb" or "wb") but can also include a compression level ("wb9") or
		a strategy: 'f' for filtered data as in "wb6f", 'h' for Huffman-only
		compression as in "wb1h", 'R' for run-length encoding as in "wb1R", or 'F'
		for fixed code compression as in "wb9F".  (See the description of
		deflateInit2 for more information about the strategy parameter.)  'T' will
		request transparent writing or appending with no compression and not using
		the gzip format.

		"a" can be used instead of "w" to request that the gzip stream that will
		be written be appended to the file.  "+" will result in an error, since
		reading and writing to the same gzip file is not supported.  The addition of
		"x" when writing will create the file exclusively, which fails if the file
		already exists.  On systems that support it, the addition of "e" when
		reading or writing will set the flag to close the file on an execve() call.

		These functions, as well as gzip, will read and decode a sequence of gzip
		streams in a file.  The append function of gzopen() can be used to create
		such a file.  (Also see gzflush() for another way to do this.)  When
		appending, gzopen does not test whether the file begins with a gzip stream,
		nor does it look for the end of the gzip streams to begin appending.  gzopen
		will simply append a gzip stream to the existing file.

		gzopen can be used to read a file which is not in gzip format; in this
		case gzread will directly read from the file without decompression.  When
		reading, this will be detected automatically by looking for the magic two-
		byte gzip header.

		gzopen returns NULL if the file could not be opened, if there was
		insufficient memory to allocate the gzFile state, or if an invalid mode was
		specified (an 'r', 'w', or 'a' was not provided, or '+' was provided).
		errno can be checked to determine if the reason gzopen failed was that the
		file could not be opened.
		*/

	     ZEXTERN gzFile ZEXPORT gzdopen OF((int fd, const char *mode));
	     /*
		gzdopen associates a gzFile with the file descriptor fd.  File descriptors
		are obtained from calls like open, dup, creat, pipe or fileno (if the file
		has been previously opened with fopen).  The mode parameter is as in gzopen.

		The next call of gzclose on the returned gzFile will also close the file
		descriptor fd, just like fclose(fdopen(fd, mode)) closes the file descriptor
		fd.  If you want to keep fd open, use fd = dup(fd_keep); gz = gzdopen(fd,
		mode);.  The duplicated descriptor should be saved to avoid a leak, since
		gzdopen does not close fd if it fails.  If you are using fileno() to get the
		file descriptor from a FILE *, then you will have to use dup() to avoid
		double-close()ing the file descriptor.  Both gzclose() and fclose() will
		close the associated file descriptor, so they need to have different file
		descriptors.

		gzdopen returns NULL if there was insufficient memory to allocate the
		gzFile state, if an invalid mode was specified (an 'r', 'w', or 'a' was not
		provided, or '+' was provided), or if fd is -1.  The file descriptor is not
		used until the next gz* read, write, seek, or close operation, so gzdopen
		will not detect if fd is invalid (unless fd is -1).
		*/

	     ZEXTERN int ZEXPORT gzbuffer OF((gzFile file, unsigned size));
	     /*
		Set the internal buffer size used by this library's functions.  The
		default buffer size is 8192 bytes.  This function must be called after
		gzopen() or gzdopen(), and before any other calls that read or write the
		file.  The buffer memory allocation is always deferred to the first read or
		write.  Three times that size in buffer space is allocated.  A larger buffer
		size of, for example, 64K or 128K bytes will noticeably increase the speed
		of decompression (reading).

		The new buffer size also affects the maximum length for gzprintf().

		gzbuffer() returns 0 on success, or -1 on failure, such as being called
		too late.
		*/

	     ZEXTERN int ZEXPORT gzsetparams OF((gzFile file, int level, int strategy));
	     /*
		Dynamically update the compression level or strategy.  See the description
		of deflateInit2 for the meaning of these parameters.  Previously provided
		data is flushed before the parameter change.

		gzsetparams returns Z_OK if success, Z_STREAM_ERROR if the file was not
		opened for writing, Z_ERRNO if there is an error writing the flushed data,
		or Z_MEM_ERROR if there is a memory allocation error.
		*/

	     ZEXTERN int ZEXPORT gzread OF((gzFile file, voidp buf, unsigned len));
	     /*
		Reads the given number of uncompressed bytes from the compressed file.  If
		the input file is not in gzip format, gzread copies the given number of
		bytes into the buffer directly from the file.

		After reaching the end of a gzip stream in the input, gzread will continue
		to read, looking for another gzip stream.  Any number of gzip streams may be
		concatenated in the input file, and will all be decompressed by gzread().
		If something other than a gzip stream is encountered after a gzip stream,
		that remaining trailing garbage is ignored (and no error is returned).

		gzread can be used to read a gzip file that is being concurrently written.
		Upon reaching the end of the input, gzread will return with the available
		data.  If the error code returned by gzerror is Z_OK or Z_BUF_ERROR, then
		gzclearerr can be used to clear the end of file indicator in order to permit
		gzread to be tried again.  Z_OK indicates that a gzip stream was completed
		on the last gzread.  Z_BUF_ERROR indicates that the input file ended in the
		middle of a gzip stream.  Note that gzread does not return -1 in the event
		of an incomplete gzip stream.  This error is deferred until gzclose(), which
		will return Z_BUF_ERROR if the last gzread ended in the middle of a gzip
		stream.  Alternatively, gzerror can be used before gzclose to detect this
		case.

		gzread returns the number of uncompressed bytes actually read, less than
		len for end of file, or -1 for error.  If len is too large to fit in an int,
		then nothing is read, -1 is returned, and the error state is set to
		Z_STREAM_ERROR.
		*/

	     ZEXTERN z_size_t ZEXPORT gzfread OF((voidp buf, z_size_t size, z_size_t nitems,
				     gzFile file));
	     /*
		Read up to nitems items of size size from file to buf, otherwise operating
		as gzread() does.  This duplicates the interface of stdio's fread(), with
		size_t request and return types.  If the library defines size_t, then
		z_size_t is identical to size_t.  If not, then z_size_t is an unsigned
		integer type that can contain a pointer.

		gzfread() returns the number of full items read of size size, or zero if
		the end of the file was reached and a full item could not be read, or if
		there was an error.  gzerror() must be consulted if zero is returned in
		order to determine if there was an error.  If the multiplication of size and
		nitems overflows, i.e. the product does not fit in a z_size_t, then nothing
		is read, zero is returned, and the error state is set to Z_STREAM_ERROR.

		In the event that the end of file is reached and only a partial item is
		available at the end, i.e. the remaining uncompressed data length is not a
		multiple of size, then the final partial item is nevetheless read into buf
		and the end-of-file flag is set.  The length of the partial item read is not
		provided, but could be inferred from the result of gztell().  This behavior
		is the same as the behavior of fread() implementations in common libraries,
		but it prevents the direct use of gzfread() to read a concurrently written
		file, reseting and retrying on end-of-file, when size is not 1.
		*/

	     ZEXTERN int ZEXPORT gzwrite OF((gzFile file,
				     voidpc buf, unsigned len));
	     /*
		Writes the given number of uncompressed bytes into the compressed file.
		gzwrite returns the number of uncompressed bytes written or 0 in case of
		error.
		*/

	     ZEXTERN z_size_t ZEXPORT gzfwrite OF((voidpc buf, z_size_t size,
				     z_size_t nitems, gzFile file));
	     /*
		gzfwrite() writes nitems items of size size from buf to file, duplicating
		the interface of stdio's fwrite(), with size_t request and return types.  If
		the library defines size_t, then z_size_t is identical to size_t.  If not,
		then z_size_t is an unsigned integer type that can contain a pointer.

		gzfwrite() returns the number of full items written of size size, or zero
		if there was an error.  If the multiplication of size and nitems overflows,
		i.e. the product does not fit in a z_size_t, then nothing is written, zero
		is returned, and the error state is set to Z_STREAM_ERROR.
		*/

	     ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
	     /*
		Converts, formats, and writes the arguments to the compressed file under
		control of the format string, as in fprintf.  gzprintf returns the number of
		uncompressed bytes actually written, or a negative zlib error code in case
		of error.  The number of uncompressed bytes written is limited to 8191, or
		one less than the buffer size given to gzbuffer().  The caller should assure
		that this limit is not exceeded.  If it is exceeded, then gzprintf() will
		return an error (0) with nothing written.  In this case, there may also be a
		buffer overflow with unpredictable consequences, which is possible only if
		zlib was compiled with the insecure functions sprintf() or vsprintf()
		because the secure snprintf() or vsnprintf() functions were not available.
		This can be determined using zlibCompileFlags().
		*/

	     ZEXTERN int ZEXPORT gzputs OF((gzFile file, const char *s));
	     /*
		Writes the given null-terminated string to the compressed file, excluding
		the terminating null character.

		gzputs returns the number of characters written, or -1 in case of error.
		*/

	     ZEXTERN char * ZEXPORT gzgets OF((gzFile file, char *buf, int len));
	     /*
		Reads bytes from the compressed file until len-1 characters are read, or a
		newline character is read and transferred to buf, or an end-of-file
		condition is encountered.  If any characters are read or if len == 1, the
		string is terminated with a null character.  If no characters are read due
		to an end-of-file or len < 1, then the buffer is left untouched.

		gzgets returns buf which is a null-terminated string, or it returns NULL
		for end-of-file or in case of error.  If there was an error, the contents at
		buf are indeterminate.
		*/

	     ZEXTERN int ZEXPORT gzputc OF((gzFile file, int c));
	     /*
		Writes c, converted to an unsigned char, into the compressed file.  gzputc
		returns the value that was written, or -1 in case of error.
		*/

	     ZEXTERN int ZEXPORT gzgetc OF((gzFile file));
	     /*
		Reads one byte from the compressed file.  gzgetc returns this byte or -1
		in case of end of file or error.  This is implemented as a macro for speed.
		As such, it does not do all of the checking the other functions do.  I.e.
		it does not check to see if file is NULL, nor whether the structure file
		points to has been clobbered or not.
		*/

	     ZEXTERN int ZEXPORT gzungetc OF((int c, gzFile file));
	     /*
		Push one character back onto the stream to be read as the first character
		on the next read.  At least one character of push-back is allowed.
		gzungetc() returns the character pushed, or -1 on failure.  gzungetc() will
		fail if c is -1, and may fail if a character has been pushed but not read
		yet.  If gzungetc is used immediately after gzopen or gzdopen, at least the
		output buffer size of pushed characters is allowed.  (See gzbuffer above.)
		The pushed character will be discarded if the stream is repositioned with
		gzseek() or gzrewind().
		*/

	     ZEXTERN int ZEXPORT gzflush OF((gzFile file, int flush));
	     /*
		Flushes all pending output into the compressed file.  The parameter flush
		is as in the deflate() function.  The return value is the zlib error number
		(see function gzerror below).  gzflush is only permitted when writing.

		If the flush parameter is Z_FINISH, the remaining data is written and the
		gzip stream is completed in the output.  If gzwrite() is called again, a new
		gzip stream will be started in the output.  gzread() is able to read such
		concatenated gzip streams.

		gzflush should be called only when strictly necessary because it will
		degrade compression if called too often.
		*/

	     /*
		ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile file,
		z_off_t offset, int whence));

		Sets the starting position for the next gzread or gzwrite on the given
		compressed file.  The offset represents a number of bytes in the
		uncompressed data stream.  The whence parameter is defined as in lseek(2);
		the value SEEK_END is not supported.

		If the file is opened for reading, this function is emulated but can be
		extremely slow.  If the file is opened for writing, only forward seeks are
		supported; gzseek then compresses a sequence of zeroes up to the new
		starting position.

		gzseek returns the resulting offset location as measured in bytes from
		the beginning of the uncompressed stream, or -1 in case of error, in
		particular if the file is opened for writing and the new starting position
		would be before the current position.
		*/

	     ZEXTERN int ZEXPORT    gzrewind OF((gzFile file));
	     /*
		Rewinds the given file. This function is supported only for reading.

		gzrewind(file) is equivalent to (int)gzseek(file, 0L, SEEK_SET)
		*/

	     /*
		ZEXTERN z_off_t ZEXPORT    gztell OF((gzFile file));

		Returns the starting position for the next gzread or gzwrite on the given
		compressed file.  This position represents a number of bytes in the
		uncompressed data stream, and is zero when starting, even if appending or
		reading a gzip stream from the middle of a file using gzdopen().

		gztell(file) is equivalent to gzseek(file, 0L, SEEK_CUR)
		*/

	     /*
		ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile file));

		Returns the current offset in the file being read or written.  This offset
		includes the count of bytes that precede the gzip stream, for example when
		appending or when using gzdopen() for reading.  When reading, the offset
		does not include as yet unused buffered input.  This information can be used
		for a progress indicator.  On error, gzoffset() returns -1.
		*/

	     ZEXTERN int ZEXPORT gzeof OF((gzFile file));
	     /*
		Returns true (1) if the end-of-file indicator has been set while reading,
		false (0) otherwise.  Note that the end-of-file indicator is set only if the
		read tried to go past the end of the input, but came up short.  Therefore,
		just like feof(), gzeof() may return false even if there is no more data to
		read, in the event that the last read request was for the exact number of
		bytes remaining in the input file.  This will happen if the input file size
		is an exact multiple of the buffer size.

		If gzeof() returns true, then the read functions will return no more data,
		unless the end-of-file indicator is reset by gzclearerr() and the input file
		has grown since the previous end of file was detected.
		*/

	     ZEXTERN int ZEXPORT gzdirect OF((gzFile file));
	     /*
		Returns true (1) if file is being copied directly while reading, or false
		(0) if file is a gzip stream being decompressed.

		If the input file is empty, gzdirect() will return true, since the input
		does not contain a gzip stream.

		If gzdirect() is used immediately after gzopen() or gzdopen() it will
		cause buffers to be allocated to allow reading the file to determine if it
		is a gzip file.  Therefore if gzbuffer() is used, it should be called before
		gzdirect().

		When writing, gzdirect() returns true (1) if transparent writing was
		requested ("wT" for the gzopen() mode), or false (0) otherwise.  (Note:
		gzdirect() is not needed when writing.  Transparent writing must be
		explicitly requested, so the application already knows the answer.  When
		linking statically, using gzdirect() will include all of the zlib code for
		gzip file reading and decompression, which may not be desired.)
		*/

	     ZEXTERN int ZEXPORT    gzclose OF((gzFile file));
	     /*
		Flushes all pending output if necessary, closes the compressed file and
		deallocates the (de)compression state.  Note that once file is closed, you
		cannot call gzerror with file, since its structures have been deallocated.
		gzclose must not be called more than once on the same file, just as free
		must not be called more than once on the same allocation.

		gzclose will return Z_STREAM_ERROR if file is not valid, Z_ERRNO on a
		file operation error, Z_MEM_ERROR if out of memory, Z_BUF_ERROR if the
		last read ended in the middle of a gzip stream, or Z_OK on success.
		*/

	     ZEXTERN int ZEXPORT gzclose_r OF((gzFile file));
	     ZEXTERN int ZEXPORT gzclose_w OF((gzFile file));
	     /*
		Same as gzclose(), but gzclose_r() is only for use when reading, and
		gzclose_w() is only for use when writing or appending.  The advantage to
		using these instead of gzclose() is that they avoid linking in zlib
		compression or decompression code that is not used when only reading or only
		writing respectively.  If gzclose() is used, then both compression and
		decompression code will be included the application when linking to a static
		zlib library.
		*/

	     ZEXTERN const char * ZEXPORT gzerror OF((gzFile file, int *errnum));
	     /*
		Returns the error message for the last error which occurred on the given
		compressed file.  errnum is set to zlib error number.  If an error occurred
		in the file system and not in the compression library, errnum is set to
		Z_ERRNO and the application may consult errno to get the exact error code.

		The application must not modify the returned string.  Future calls to
		this function may invalidate the previously returned string.  If file is
		closed, then the string previously returned by gzerror will no longer be
		available.

		gzerror() should be used to distinguish errors from end-of-file for those
		functions above that do not distinguish those cases in their return values.
		*/

	     ZEXTERN void ZEXPORT gzclearerr OF((gzFile file));
	     /*
		Clears the error and end-of-file flags for file.  This is analogous to the
		clearerr() function in stdio.  This is useful for continuing to read a gzip
		file that is being written concurrently.
		*/

#endif /* !Z_SOLO */

	     /* checksum functions */

	     /*
		These functions are not related to compression but are exported
		anyway because they might be useful in applications using the compression
		library.
		*/

	     ZEXTERN uLong ZEXPORT adler32 OF((uLong adler, const Bytef *buf, uInt len));
	     /*
		Update a running Adler-32 checksum with the bytes buf[0..len-1] and
		return the updated checksum.  If buf is Z_NULL, this function returns the
		required initial value for the checksum.

		An Adler-32 checksum is almost as reliable as a CRC-32 but can be computed
		much faster.

		Usage example:

		uLong adler = adler32(0L, Z_NULL, 0);

		while (read_buffer(buffer, length) != EOF) {
		adler = adler32(adler, buffer, length);
		}
		if (adler != original_adler) error();
		*/

	     ZEXTERN uLong ZEXPORT adler32_z OF((uLong adler, const Bytef *buf,
				     z_size_t len));
	     /*
		Same as adler32(), but with a size_t length.
		*/

	     /*
		ZEXTERN uLong ZEXPORT adler32_combine OF((uLong adler1, uLong adler2,
		z_off_t len2));

		Combine two Adler-32 checksums into one.  For two sequences of bytes, seq1
		and seq2 with lengths len1 and len2, Adler-32 checksums were calculated for
		each, adler1 and adler2.  adler32_combine() returns the Adler-32 checksum of
		seq1 and seq2 concatenated, requiring only adler1, adler2, and len2.  Note
		that the z_off_t type (like off_t) is a signed integer.  If len2 is
		negative, the result has no meaning or utility.
		*/

	     ZEXTERN uLong ZEXPORT crc32   OF((uLong crc, const Bytef *buf, uInt len));
	     /*
		Update a running CRC-32 with the bytes buf[0..len-1] and return the
		updated CRC-32.  If buf is Z_NULL, this function returns the required
		initial value for the crc.  Pre- and post-conditioning (one's complement) is
		performed within this function so it shouldn't be done by the application.

		Usage example:

		uLong crc = crc32(0L, Z_NULL, 0);

		while (read_buffer(buffer, length) != EOF) {
		crc = crc32(crc, buffer, length);
		}
		if (crc != original_crc) error();
		*/

	     ZEXTERN uLong ZEXPORT crc32_z OF((uLong adler, const Bytef *buf,
				     z_size_t len));
	     /*
		Same as crc32(), but with a size_t length.
		*/

	     /*
		ZEXTERN uLong ZEXPORT crc32_combine OF((uLong crc1, uLong crc2, z_off_t len2));

		Combine two CRC-32 check values into one.  For two sequences of bytes,
		seq1 and seq2 with lengths len1 and len2, CRC-32 check values were
		calculated for each, crc1 and crc2.  crc32_combine() returns the CRC-32
		check value of seq1 and seq2 concatenated, requiring only crc1, crc2, and
		len2.
		*/


	     /* various hacks, don't look :) */

	     /* deflateInit and inflateInit are macros to allow checking the zlib version
	      * and the compiler's view of z_stream:
	      */
	     ZEXTERN int ZEXPORT deflateInit_ OF((z_streamp strm, int level,
				     const char *version, int stream_size));
	     ZEXTERN int ZEXPORT inflateInit_ OF((z_streamp strm,
				     const char *version, int stream_size));
	     ZEXTERN int ZEXPORT deflateInit2_ OF((z_streamp strm, int  level, int  method,
				     int windowBits, int memLevel,
				     int strategy, const char *version,
				     int stream_size));
	     ZEXTERN int ZEXPORT inflateInit2_ OF((z_streamp strm, int  windowBits,
				     const char *version, int stream_size));
	     ZEXTERN int ZEXPORT inflateBackInit_ OF((z_streamp strm, int windowBits,
				     unsigned char FAR *window,
				     const char *version,
				     int stream_size));
#ifdef Z_PREFIX_SET
#  define z_deflateInit(strm, level) \
	     deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
#  define z_inflateInit(strm) \
	     inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
#  define z_deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
	     deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
			     (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
#  define z_inflateInit2(strm, windowBits) \
	     inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
			     (int)sizeof(z_stream))
#  define z_inflateBackInit(strm, windowBits, window) \
	     inflateBackInit_((strm), (windowBits), (window), \
			     ZLIB_VERSION, (int)sizeof(z_stream))
#else
#  define deflateInit(strm, level) \
	     deflateInit_((strm), (level), ZLIB_VERSION, (int)sizeof(z_stream))
#  define inflateInit(strm) \
	     inflateInit_((strm), ZLIB_VERSION, (int)sizeof(z_stream))
#  define deflateInit2(strm, level, method, windowBits, memLevel, strategy) \
	     deflateInit2_((strm),(level),(method),(windowBits),(memLevel),\
			     (strategy), ZLIB_VERSION, (int)sizeof(z_stream))
#  define inflateInit2(strm, windowBits) \
	     inflateInit2_((strm), (windowBits), ZLIB_VERSION, \
			     (int)sizeof(z_stream))
#  define inflateBackInit(strm, windowBits, window) \
	     inflateBackInit_((strm), (windowBits), (window), \
			     ZLIB_VERSION, (int)sizeof(z_stream))
#endif

#ifndef Z_SOLO

	     /* gzgetc() macro and its supporting function and exposed data structure.  Note
	      * that the real internal state is much larger than the exposed structure.
	      * This abbreviated structure exposes just enough for the gzgetc() macro.  The
	      * user should not mess with these exposed elements, since their names or
	      * behavior could change in the future, perhaps even capriciously.  They can
	      * only be used by the gzgetc() macro.  You have been warned.
	      */
	     struct gzFile_s {
		     unsigned have;
		     unsigned char *next;
		     z_off64_t pos;
	     };
	     ZEXTERN int ZEXPORT gzgetc_ OF((gzFile file));  /* backward compatibility */
#ifdef Z_PREFIX_SET
#  undef z_gzgetc
#  define z_gzgetc(g) \
	     ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
#else
#  define gzgetc(g) \
	     ((g)->have ? ((g)->have--, (g)->pos++, *((g)->next)++) : (gzgetc)(g))
#endif

	     /* provide 64-bit offset functions if _LARGEFILE64_SOURCE defined, and/or
	      * change the regular functions to 64 bits if _FILE_OFFSET_BITS is 64 (if
	      * both are true, the application gets the *64 functions, and the regular
	      * functions are changed to 64 bits) -- in case these are set on systems
	      * without large file support, _LFS64_LARGEFILE must also be true
	      */
#ifdef Z_LARGE64
	     ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
	     ZEXTERN z_off64_t ZEXPORT gzseek64 OF((gzFile, z_off64_t, int));
	     ZEXTERN z_off64_t ZEXPORT gztell64 OF((gzFile));
	     ZEXTERN z_off64_t ZEXPORT gzoffset64 OF((gzFile));
	     ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off64_t));
	     ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off64_t));
#endif

#if !defined(ZLIB_INTERNAL) && defined(Z_WANT64)
#  ifdef Z_PREFIX_SET
#    define z_gzopen z_gzopen64
#    define z_gzseek z_gzseek64
#    define z_gztell z_gztell64
#    define z_gzoffset z_gzoffset64
#    define z_adler32_combine z_adler32_combine64
#    define z_crc32_combine z_crc32_combine64
#  else
#    define gzopen gzopen64
#    define gzseek gzseek64
#    define gztell gztell64
#    define gzoffset gzoffset64
#    define adler32_combine adler32_combine64
#    define crc32_combine crc32_combine64
#  endif
#  ifndef Z_LARGE64
	     ZEXTERN gzFile ZEXPORT gzopen64 OF((const char *, const char *));
	     ZEXTERN z_off_t ZEXPORT gzseek64 OF((gzFile, z_off_t, int));
	     ZEXTERN z_off_t ZEXPORT gztell64 OF((gzFile));
	     ZEXTERN z_off_t ZEXPORT gzoffset64 OF((gzFile));
	     ZEXTERN uLong ZEXPORT adler32_combine64 OF((uLong, uLong, z_off_t));
	     ZEXTERN uLong ZEXPORT crc32_combine64 OF((uLong, uLong, z_off_t));
#  endif
#else
	     ZEXTERN gzFile ZEXPORT gzopen OF((const char *, const char *));
	     ZEXTERN z_off_t ZEXPORT gzseek OF((gzFile, z_off_t, int));
	     ZEXTERN z_off_t ZEXPORT gztell OF((gzFile));
	     ZEXTERN z_off_t ZEXPORT gzoffset OF((gzFile));
	     ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
	     ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));
#endif

#else /* Z_SOLO */

	     ZEXTERN uLong ZEXPORT adler32_combine OF((uLong, uLong, z_off_t));
	     ZEXTERN uLong ZEXPORT crc32_combine OF((uLong, uLong, z_off_t));

#endif /* !Z_SOLO */

	     /* undocumented functions */
	     ZEXTERN const char   * ZEXPORT zError           OF((int));
	     ZEXTERN int            ZEXPORT inflateSyncPoint OF((z_streamp));
	     ZEXTERN const z_crc_t FAR * ZEXPORT get_crc_table    OF((void));
	     ZEXTERN int            ZEXPORT inflateUndermine OF((z_streamp, int));
	     ZEXTERN int            ZEXPORT inflateValidate OF((z_streamp, int));
	     ZEXTERN unsigned long  ZEXPORT inflateCodesUsed OF ((z_streamp));
	     ZEXTERN int            ZEXPORT inflateResetKeep OF((z_streamp));
	     ZEXTERN int            ZEXPORT deflateResetKeep OF((z_streamp));
#if (defined(_WIN32) || defined(__CYGWIN__)) && !defined(Z_SOLO)
	     ZEXTERN gzFile         ZEXPORT gzopen_w OF((const wchar_t *path,
				     const char *mode));
#endif
#if defined(STDC) || defined(Z_HAVE_STDARG_H)
#  ifndef Z_SOLO
	     ZEXTERN int            ZEXPORTVA gzvprintf Z_ARG((gzFile file,
				     const char *format,
				     va_list va));
#  endif
#endif

#ifdef __cplusplus
}
#endif

#endif /* ZLIB_H */
